Feat: add hover boxes and diagnostics from lsp

include/spans.h

@@ -0,0 +1,101 @@
+#ifndef SPANS_H
+#define SPANS_H
+
+#include "./pch.h"
+#include "./utils.h"
+
+struct VWarn {
+  uint32_t line;
+  std::string text;
+  std::string text_full;
+  std::string source;
+  std::string code;
+  std::vector<std::string> see_also;
+  int8_t type;
+  uint32_t start;
+  uint32_t end{UINT32_MAX};
+
+  bool operator<(const VWarn &other) const { return line < other.line; }
+};
+
+struct VAI {
+  Coord pos;
+  char *text;
+  uint32_t len;
+  uint32_t lines; // number of \n in text for speed .. the ai part will not
+                  // line wrap but multiline ones need to have its own lines
+                  // after the first one
+};
+
+struct Fold {
+  uint32_t start;
+  uint32_t end;
+
+  bool contains(uint32_t line) const { return line >= start && line <= end; }
+  bool operator<(const Fold &other) const { return start < other.start; }
+};
+
+struct Span {
+  uint32_t start;
+  uint32_t end;
+  Highlight *hl;
+
+  bool operator<(const Span &other) const { return start < other.start; }
+};
+
+struct Spans {
+  std::vector<Span> spans;
+  Queue<std::pair<uint32_t, int64_t>> edits;
+  bool mid_parse = false;
+  std::shared_mutex mtx;
+};
+
+struct SpanCursor {
+  Spans &spans;
+  size_t index = 0;
+  std::vector<Span *> active;
+  std::shared_lock<std::shared_mutex> lock;
+
+  SpanCursor(Spans &s) : spans(s) {}
+  Highlight *get_highlight(uint32_t byte_offset) {
+    for (int i = (int)active.size() - 1; i >= 0; i--)
+      if (active[i]->end <= byte_offset)
+        active.erase(active.begin() + i);
+    while (index < spans.spans.size() &&
+           spans.spans[index].start <= byte_offset) {
+      if (spans.spans[index].end > byte_offset)
+        active.push_back(const_cast<Span *>(&spans.spans[index]));
+      index++;
+    }
+    Highlight *best = nullptr;
+    int max_prio = -1;
+    for (auto *s : active)
+      if (s->hl->priority > max_prio) {
+        max_prio = s->hl->priority;
+        best = s->hl;
+      }
+    return best;
+  }
+  void sync(uint32_t byte_offset) {
+    lock = std::shared_lock(spans.mtx);
+    active.clear();
+    size_t left = 0, right = spans.spans.size();
+    while (left < right) {
+      size_t mid = (left + right) / 2;
+      if (spans.spans[mid].start <= byte_offset)
+        left = mid + 1;
+      else
+        right = mid;
+    }
+    index = left;
+    while (left > 0) {
+      left--;
+      if (spans.spans[left].end > byte_offset)
+        active.push_back(const_cast<Span *>(&spans.spans[left]));
+      else if (byte_offset - spans.spans[left].end > 1000)
+        break;
+    }
+  }
+};
+
+#endif